The Lady's guide to Modern Manners

What do you suggest about splitting the bill in restaurants? Usually it gets divided equally regardless of whether I've had a whole lot more or a whole lot less than everyone else. I'm either guilty or fuming. Of course, you don't want to be thought mean. Money, like sex, is one of the great driving forces. People fall out over it all too easily.

Bridget Copley, Hertfordshire

Dear Bridget,

On the whole, when going Dutch in restaurants, the bill is divided equally. It can be a time-consuming, mathematical nightmare if people start saying, 'My main was £18.75; yours was £19.95.' What was supposed to be a happy social occasion is soon drained of all jollity. Surely it's best to share? Isn't that the point of being there?

But conspicuous consumers of extras which the others did not have – such as gin and tonic before the meal, brandy afterwards etc – should pay up. They rarely do though and if you dare to mention their presumption they'll almost certainly mark you down as mean – when actually they are the ones being mean.

Money goes deep. Odd behaviour over it arises often from childhood anxiety of some kind and has nothing to do with how much money someone has actually got. We have to be forgiving.

It's thoughtful and considerate to offer to pay for your extras. But don't worry if the offer is refused. Your gesture will be appreciated.

On a more general point, offers to pay for cinema tickets, petrol, parking, taxis, etc, often are refused. Or a friend undertakes unexpectedly to foot the entire restaurant bill. This worries some, I know. They don't like to be obliged. But maybe there's more generosity in the world than we think.

If you're caught up in one of those large groups that spontaneously decides to go en masse to a restaurant – but you're not feeling very hungry, well, just don't go. Especially if you don't want to fork out for everyone else's three courses

Alternatively: go with your group to an eaterie but make it very clear in advance that you're just having a salad and that's all you're paying for. You could be mock-school marmish about this if you felt up to it. Mention it several times more during the meal and then, when the bill comes, the people sitting near you will back you up. A lot of us, especially these days, are genuinely hard up. I sat down in a restaurant this year with someone who said, as the menus were handed, 'I can only afford to pay £15.' This is an excellent approach. By the same token it is important to re-pay small debts promptly and not subject the lender to the embarrassment of having to ask.

Please send your questions to Thomas.blaikie@lady.co.uk or write to him at The Lady, 39-40 Bedford Street, London WC2E 9ER.

WHAT TO DO ABOUT... Supermarket behaviour

What to do if you spot someone over-enthusiastically squeezing fruit in the supermarket; then putting it back? Why not take the opportunity for banter, so rarely seen in supermarkets owing to shoppers being under intense pressure to give a dinner party, feed their children, etc? Provided the person doesn't look, well, disturbed or dangerous (as wildly rude people might be), you could say airily: 'I was thinking of doing something with avos. Aren't they any good then?' There might not be an immediate response but you could warm to your theme of avos or whatever fruit or veg is in question. There could be discussion of recipes, recall of fruit/veg disasters from your past, hopes for the future, etc.

I bet you anything, sooner or later you'll be rewarded with a gleam of guilt. They might even say, 'I hope I haven't spoilt them.' And who knows, they might not do it again.

Second only to motoring, supermarkets are the prime location for rudeness in our society. In supermarkets, we disappear into tunnels of shopping desperation and blank each other. So the more conversational opportunities you can exploit in the aisles the better.